新闻听力 | 香烟如何影响身体？
香烟如何影响身体？How do cigarettes affect the body?常速 | 七级（偏易）| 699词 | 4min49s刘立军供稿Part I. QUESTIONSListen to the interview and choose the best answer to each question you hear.Q1. What substance in cigarettes is responsible for making smoking highly addictive? A. Tar. B. Carbon monoxide. C. Nicotine. D. Arsenic. Q2. What is one of the immediate physical benefits of quitting smoking? A. Improved eyesight and bone strength. B. Stabilization of carbon monoxide levels. C. Restoration of DNA repair processes. D. Reduced risk of erectile dysfunction. Q3. What happens to the cilia in the lungs after quitting smoking for 9 months? A. They are permanently damaged. B. They start producing harmful chemicals. C. They become less effective in cleaning airways. D. They are restored and improve resistance to infection. Q4. What can be inferred about the long-term effects of quitting smoking? A. Quitting smoking has no impact on coronary heart disease. B. The body gradually regains its ability to repair DNA. C. Lung cancer risk remains unchanged after quitting smoking. D. The benefits of quitting smoking are limited to younger smokers. Q5. What is the main purpose of the text? A. To highlight the dangers of smoking and benefits of quitting. B. To explain the chemical composition of cigarettes. C. To discuss the psychological challenges of quitting smoking. D. To analyze the global impact of smoking-related diseases. Part II. TRANSCRIPTHow do cigarettes affect the body?Cigarettes aren’t good for us. That’s hardly news — we’ve known about the dangers of smoking for decades. But how exactly do cigarettes harm us? Let’s look at what happens as their ingredients make their way through our bodies, and how we benefit physically when we finally give up smoking.With each inhalation, smoke brings its more than 5,000 chemical substances into contact with the body’s tissues. From the start, tar, a black, resinous material, begins to coat the teeth and gums, damaging tooth enamel, and eventually causing decay. Over time, smoke also damages nerve-endings in the nose, causing loss of smell.Inside the airways and lungs, smoke increases the likelihood of infections, as well as chronic diseases like bronchitis and emphysema. It does this by damaging the cilia, tiny hairlike structures whose job it is to keep the airways clean. It then fills the alveoli, tiny air sacs that enable the exchange of oxygen and carbon dioxide between the lungs and blood. A toxic gas called carbon monoxide crosses that membrane into the blood, binding to hemoglobin and displacing the oxygen it would usually have transported around the body. That’s one of the reasons smoking can lead to oxygen deprivation and shortness of breath.bronchitis n. 支气管炎 emphysema n. 肺气肿 alveoli n. 肺泡 sac n. 囊，气囊 membrane n. 膜 hemoglobin n. 血红蛋白 (Q1) Within about 10 seconds, the bloodstream carries a stimulant called nicotine to the brain, triggering the release of dopamine and other neurotransmitters including endorphins that create the pleasurable sensations which make smoking highly addictive. Nicotine and other chemicals from the cigarette simultaneously cause constriction of blood vessels and damage their delicate endothelial lining, restricting blood flow. These vascular effects lead to thickening of blood vessel walls and enhance blood platelet stickiness, increasing the likelihood that clots will form and trigger heart attacks and strokes.dopamine n. 多巴胺 neurotransmitter n. 神经递质 endorphin n. 内啡肽 endothelial adj. 内皮的 lining n. 内衬，内膜 Many of the chemicals inside cigarettes can trigger dangerous mutations in the body’s DNA that make cancers form. Additionally, ingredients like arsenic and nickel may disrupt the process of DNA repair, thus compromising the body’s ability to fight many cancers. In fact, about one of every three cancer deaths in the United States is caused by smoking.And it’s not just lung cancer. Smoking can cause cancer in multiple tissues and organs, as well as damaged eyesight and weakened bones. It makes it harder for women to get pregnant. And in men, it can cause erectile dysfunction.dysfunction n. 功能障碍 But for those who quit smoking, there’s a huge positive upside with almost immediate and long-lasting physical benefits.Just 20 minutes after a smoker’s final cigarette, their heart rate and blood pressure begin to return to normal. (Q2) After 12 hours, carbon monoxide levels stabilize, increasing the blood’s oxygen-carrying capacity. A day after ceasing, heart attack risk begins to decrease as blood pressure and heart rates normalize. After two days, the nerve endings responsible for smell and taste start to recover.Lungs become healthier after about one month, with less coughing and shortness of breath. (Q3) The delicate hair-like cilia in the airways and lungs start recovering within weeks, and are restored after 9 months, improving resistance to infection.cilia n. 纤毛 By the one-year anniversary of quitting, heart disease risk plummets to half as blood vessel function improves. Five years in, the chance of a clot forming dramatically declines, and the risk of stroke continues to reduce. (Q4) After ten years, the chances of developing fatal lung cancer go down by 50%, probably because the body’s ability to repair DNA is once again restored. Fifteen years in, the likelihood of developing coronary heart disease is essentially the same as that of a non-smoker.plummet v. 暴跌，骤降 coronary adj. 冠状的，冠状动脉的 There’s no point pretending this is all easy to achieve. Quitting can lead to anxiety and depression, resulting from nicotine withdrawal. But fortunately, such effects are usually temporary. And quitting is getting easier, thanks to a growing arsenal of tools. Nicotine replacement therapy through gum, skin patches, lozenges, and sprays may help wean smokers off cigarettes. They work by stimulating nicotine receptors in the brain and thus preventing withdrawal symptoms, without the addition of other harmful chemicals. Counselling and support groups, cognitive behavioral therapy, and moderate intensity exercise also help smokers stay cigarette-free.lozenge n. 含片，润喉片 wean v. 使断奶，使戒掉 That’s good news, since quitting puts you and your body on the path back to health.Part III. KEYQ1. C.【解析】细节题。根据“Within about 10 seconds, the bloodstream carries a stimulant called nicotine to the brain, triggering the release of dopamine and other neurotransmitters.”，可知血液将一种叫尼古丁的刺激物输送到大脑，触发多巴胺和其他神经递质的释放，使人吸烟成瘾。正确答案为C。 Q2. B.【解析】细节题。根据“After 12 hours, carbon monoxide levels stabilize, increasing the blood’s oxygen-carrying capacity.”，可知在戒烟后12小时，血液中的一氧化碳水平稳定下来，增加了血液携带氧气的能力，是戒烟后即时身体益处。正确答案为B。 Q3. D.【解析】细节题。根据“The delicate hair-like cilia in the airways and lungs start recovering within weeks, and are restored after 9 months, improving resistance to infection.”，可知呼吸道和肺部的纤毛在几周内开始恢复，并在9个月后恢复，提高了对感染的抵抗力。正确答案为D。 Q4. B.【解析】推理题。根据“After ten years, the chances of developing fatal lung cancer go down by 50%, probably because the body’s ability to repair DNA is once again restored.”，可知在戒烟十年后，患致命肺癌的几率下降了50%，可能是因为身体修复DNA的能力再次恢复。从中可以推断，戒烟后身体会逐渐恢复修复DNA的能力。正确答案为B。 Q5. A.【解析】主旨题。文章主要讨论了吸烟对身体的危害以及戒烟带来的健康益处处。正确答案为A。 （本文图片来源于摄图网，版权归摄图网所有)